Buckle chute folding machines are well known in the printing and mail service fields. Conventional buckle chutes are generally provided with straight or curved configurations which confine the paper as it is buckled and advanced to the nip of folding rollers. In machines which employ chutes having convex or straight configurations--two sided chutes--it is necessary to confine both sides of the paper to maintain it in proper orientation in the paper pathway. One sided chutes which have concave configurations confine the paper on one side.
In practice, two-sided buckle chutes must be removed or at least opened to permit the extraction of jammed or misfolded paper. As a consequence, the chutes cannot be utilized as support structures in the machine. In order to permit removal of the chutes, separate support structure must be provided to maintain the integrity of the machine. Further, when the chutes are removed, a mechanism is required to permit reinstallation of the chutes without requirement of complex tuning and adjustments.
Two-sided chutes have also proved unsatisfactory for use in precision folding operations. Conventional two-sided chute folding apparatus confine the paper as it advances into the chute and is thereafter fed into folding rollers. Confinement of the paper as it advances to the folding rollers generates a ripple in the paper which varies the length of fold panels in the paper. Correction to take account of this ripple effect requires adjustment of the chute apparatus to take account of the characteristics of the paper and environmental factors such as humidity.
Fixed two sided chutes permit a less expensive, folding machine design since the base of the chutes can be utilized to space and secure side frames of the machine together. However, such machines have not proved entirely satisfactory in that they do not permit ready access to the paper pathway for jam clearance. Moreover, such fixed chute arrangements generally require the operator to reverse the direction flow of paper in the machine to clear a paper jam.
The present invention is directed to a one-sided open buckle chute apparatus which advances the prior art by being less expensive and by providing ready access to a paper pathway for jam clearance. An open chute design provides further advantage by facilitating use of the apparatus to effect secondary operations on the paper. For example, as the paper travels through the folding stations of the apparatus, the open chute design permits application of glue to paper folds.
Accordingly, it is a broad object of the present invention to provide an improved buckle chute paper folding apparatus of compact design which effects precision paper folds.
A more specific object of the invention is to provide a paper folding apparatus in which access to the paper pathway for jam clearance is readily effected without removal or disassembly of buckle chutes and access covers for economies in maintenance and manufacture.
A further object of the invention is to provide a paper folding apparatus in which paper jams may be readily cleared without readjustment of fold mechanisms.
A still further object of the invention is to provide an open buckle chute apparatus which provides ready access to paper during folding operations to facilitate performance of secondary paper operations.